Field Journal 4
Field Journal 4
3/12/20
Time: 8:15 am
Date: 4 April 2020
Location: Silvio Conte Wildlife Refuge, Hadley, MA
Temperature: 43℉
Cloud cover: 95% cloud cover
Wind: none
The morning was calm and still as my mom and I set off down a wooded trail in the Conte Wildlife Refuge. The woods consisted mainly of young birches and sumac and little wetlands, surrounded by large fields. Singing song sparrows greeted us, perched on low-growing plants near the forest edge. Although not obligate migrants, some song sparrows may have overwintered as Far south as Florida (1,300 miles from Massachusetts). Mourning doves and robins flew overhead, both congregating in flocks. In previous bird walks, I had not seen as many same-species flocks as I did on this one. Perhaps larger flocks are becoming more common as food resources are becoming more abundant and evenly distributed with warmer days. Spring is certainly here- I saw many trout lily leaves, red maple flowers, greenish-yellow willow buds, and heard a spring peeper.
I saw what I thought was a flock of robins perched in a birch, but after taking their picture and zooming in for a closer look, I was happy to discover that they were Cedar Waxwings. In contrast to the active and vocal robins, jays, doves and sparrows, the cedar waxwings were still and silent. If these birds recently flew up from their non-breeding range south of North Carolina, then they could have flown over 600 miles to reach western Massachusetts.
Once the trail became more heavily wooded, I spotted a Downy Woodpecker and many Eastern Phoebes. Downy Woodpeckers are year-round residents that are able to forage for food through the northern winters. They are well adapted to endure northern winters on a diet of insect larvae, berries, seeds, and acorns, and they are a common participant in mixed-species flocks, which offer better foraging-efficiency and protection to overwintering birds. Although winters are energetically costly and risky to year-round residents such as Downy Woodpeckers, they benefit from good access to nest sites early in the year and do not have to deal with the energy costs and high mortality rates of a long migration. Birds such as the Eastern Phoebes do not have the option to overwinter in Massachusetts due to a lack of flis to catch. The flycatchers I observed in Early April will have better access to nesting sites but less access to food than those arriving later in the spring. I noted a small swarm of bugs later on my walk, however, indicating that flycatchers indeed have a small food supply at this time of year. These Phoebes could have recently arrived from anywhere between Virginia and central Mexico. (From Massachusetts to Florida is 1,300 miles).
Reaching a river running through a tall pine stand, I observed a female mallard sitting on a downed tree in a river and a flock of jays flying loudly from a tall pine tree. We came upon an overlook to a large field, which was full of robins and a few red-winged blackbirds pecking at the ground. My mom noted that these robins looked smaller than the robins she had seen throughout the winter. Perhaps these particular robins were making their way back north and the strenuous flight had used the bulk of their fat reserves. Alternatively, they may have been the same birds she had seen earlier in the winter but had since lost their fat reserves. The wintering range of Robins extends as far south as Florida, although these birds probably would be coming from a closer state to minimize their flight distance. Robins that overwinter in the north benefit from early access to food and breeding resources in the spring at the cost of enduring harsh weather and food scarcity through the winter. Robins that migrate south for the winter do so to decrease their competition for food and exposure to unfavorable climates over the winter, but at the cost of a dangerous migratory flight and reduced access to breeding sites upon their return. Back in the woods, I came across a pond with three male mallards and a downy woodpecker hopping along the bank.
Leaving the woods, we walked down a road lined with willows and surrounded by large fields. Red-winged Blackbirds were everywhere, as well as a few tufted titmice. A small bird flew overhead, and its graceful movement was different from that of the blackbirds. A photo revealed it to be a female American Kestrel! A zoom lens had proved to be a useful ID tool for the second time during this walk. A camera was especially helpful on such a cloudy day, when most birds appeared as dark silhouettes against the grey clouds.
An interesting note about the location of my bird walk is that a barn on the refuge property houses one of the largest barn swallow colonies in Massachusetts. Sadly, the barn is in disrepair, and after much controversy between swallow advocates and the Fish and Wildlife service (who do not have the budget to maintain the decrepit barn), the barn and its colony are to be demolished this year. I did not see any swallows on my walk because they are obligate migrants, and the bugs that sustain them are not available in Massachusetts yet. However, more insects are starting to emerge earlier in the spring due to a warming climate, and the resulting phenological mismatch between insects and bird migration may contribute to recent flycatcher declines. Swallow populations have declined by 50% since the 1990’s.
The total migration miles traveled by the individuals I observed on my walk is about
= 15 robins (assuming only half migrated) * 700 miles
10 Red-winged Blackbirds (assuming half migrated) * 300 miles
6 Eastern Phoebes * 1000 miles
7 song sparrows (assuming half migrated) * 800 miles
10 cedar waxwings * 600 miles
= 31,100 miles total. That’s pretty far. Equivalent of going to California and back like 5 times.
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